Zinc fluoride
borophosphate (ZFBP) glasses doped with tripositive praseodymium and neodymium
ions have been prepared by melt quenching technique. The final composition of
glasses in mol.% is 15.44 B2O3 – 39.77 P2O5
-17.36 Na2O – 16.67 Al2O3 – 10.74 ZnF2
– R Ln
(where R= 0.0, 0.1, 0.3 and 0.5 mol % and Ln = Pr3+ and Nd3+).
The absorption spectra of doped ZFBP glasses have been recorded at room
temperature. Eight absorption bands have been observed from the ground state 3H4
to excited states 3F2, 3F3, 3F4,
1G4,1D2, 3P0,
3P1 and 3P2 in Pr3+
doped ZFBP glasses and twelve absorption bands from the ground state 4I9/2
to excited states 4F3/2, 4F5/2, 4F7/2,
4S3/2, 4F9/2, 2H11/2,
4G5/2, 4G7/2, 4G9/2,
2G9/2, 4G11/2, and 2P1/2
in the case of Nd3+ doped ZFBP glasses. From these spectral data
various energy interaction parameters like Slater-Condon parameter Fk (k=2, 4, 6), Lande´ parameter ξ4f and Racah parameters Ek (k=1,2,3) have been computed. Nephelauxetic ratio (') and bonding parameters (b1/2)
have also been computed from these parameters to study the nature of bonding in
doped glasses. The intensities of the f-f transitions in the absorption spectra
have been analyzed by the application of the Judd-Ofelt theory. J-O parameters (Ωλ) have been computed. Ωλ parameters of ZFBP glasses have
been compared with those of similar glasses to infer the nature of bonding in
these glasses.